Coil spring winding machine with bar transfer means

ABSTRACT

IN A COIL SPRING WINDING MACHINE HAVING A MANDREL ROTATABLE AT A CONSTANT SPEED AND A ROD STOCK GUIDE ADAPTED FOR LINEAR TRAVEL LONGITUDINALLY OF SAID MANDREL AT VARIABLE SPEEDS FOR PITCH CONTROL OF THE SPRING TO BE FORMED, A BAR TRANSFER ASSEMBLY CARRIED BY SAID ROD STOCK GUIDE AND BEING MOVABLE WITH REAPECT THERETO FOR REGULATING THE HELICAL ANGLES ON WHICH THE SPRING IS FORMED. A ROLLER IS PROVIDED ON SAID GUIDE FOR TRAVEL THEREWITH TO ENGAGE THE STOCK AS FED TO THE MACHINE TO CONTROL TRANSITION PITCHES.

Oct. 5, 1971 COIL SPRING WINDING MACHINE WITH BAR TRANSFER MEANS W. A.SCHEUBLEIN, JR,

ETAL

Filed Sept. 8. 1969 3 Sheets-Sheet 1 75 20 J (9 5 z /r /7 4 a F IG.|

4 Lu I 4 /4 \4 7 o FIG. s 20 5 I l I SERVO LEAD SCREW ASSEMBLY SYSTEM HII I 65 HYDRAULIC POWER 2:29 MANDREL TRANSDUCER SOURCE PRESET- sPRINGPRESET -E SERVO G 4 DATA COUNTER VOLTAGE AMPLIFIER I I {CIRCUIT MENT I LJ 45 66 67 37 I P g I f g E E I [TABLET SERVO 'B J P CARRIAGE l $8'ffiAMP F 5 ASSEM- -C|RCUIT MENT IRAII SFER BLY CONSOLE ASSEMBLY INVENTORS 6WILLIAM A. SCHEUBLEIN, JR.

QM Kw ATTORNEY 1971 w. A. SCHEUBLEIN. JR., ETAL 3,610,006

COIL SPRING WINDING MACHINE WITH BAR TRANSFER MEANS Filed Sept. 8. 19693 Sheets-Sheet B F|G.2 ZZ\ 47 J r FIG.3

W l.- INVENTORS 4 WILLIAM A. SCHEUBLEIN, JR. Louls. P. FISTER JAMES A.MCNEELY JAY Y V. TALMAGE QM (M ATTORNEY Oct. 5, 1971 w. A. SCHEUBLEIN,JR., E 3,610,005

COIL SPRING WINDING MACHINE WITH BAR TRANSFER MEANS Filed Sept. 8, 19693 Sheets-Sheet Z INVENTORS WILLIAM A. SCHEUBLEIN, JR.

LOUIS P. FISTER JAMES A. MCNEELY JAY V1. TALMAGE ATTORNEY United StatesPatent 3,610,006 COIL SPRING WINDING MACHINE WITH BAR TRANSFER MEANSWilliam A. Scheublein, Jr., Ballwin, Louis P. Fister, St. Louis, JamesA. McNeely, Manchester, and Jay W. Talmage, Berkeley, Mo., assignors toMoog Industries, Inc., Wellston, Mo. Continuation-impart of applicationSer. No. 611,210, Jan. 3, 1967. This application Sept. 8, 1969, Ser. No.855,833

Int. Cl. B21j 7/26, 3/]() US. CI. 7222 9 Claims ABSTRACT OF THEDISCLOSURE BACKGROUND AND SUMMARY OF THE INVENTION This inventionrelates in general to coil spring winding machines and, moreparticularly, to bar transfer means for controlling the helical angle orangles of the formed coils. This application is a continuation-in-partof our copending patent application Ser. No. 611,210, now Pat. No.3,470,721, filed Jan. 3, 1967, upon a Coil Spring Winding Machine.

It is an object of the present invention to provide a machine forproducing compression coil spring having a unique rod stock controldevice to assure proper feeding of the stock to the mandrel fordeveloping the predetermined helical angle of the coil or coils beingformed.

It is a further object of the present invention to provide a machine ofthe character stated wherein the rod stock control device is adapted forautomatic positionment during the spring forming operation to allow foran infinite variation in the helic angles.

It is another object of the present invention to provide a controldevice of the character stated which may be incorporated in existingcoil winding machines wherein the forming mandrel serves as thecommanding source without requiring costly modification.

It is a further object of the present invention to provide in a coilspring winding machine a work engaging member located with respect tothe forming mandrel so as to control the transition pitches of thespring being formed.

It is a further object of the present invention to provide workcontrolling means for a coil spring winding machine which is reliable,durable, and fully effective in use; and which is adapted forprogramming so as to be automatically operative.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front perspective view ofa coil spring wind ing machine having bar transfer means constructed inaccordance with and embodying the present invention.

FIG. 2 is a fragmentary, enlarged front view of the bar transferassembly, illustrating the same after the first quarter turn of themandrel.

FIG. 3 is a fragmentary front view of the bar transfer assemblyillustrating same in one operative position.

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FIG. 4 is a vertical transverse sectional view taken on the line 4-4 ofFIG. 3.

FIG. 5 is a fragmentary plan view taken on the line 5-5 of FIG. 4.

FIG. 6 is a block diagram of the primary components of the machine.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now by referencenumerals to the drawings which illustrate the preferred embodiment ofthe present invention, A generally designates a coil spring windingmachine adapted for producing coil springs, as used for automobilesuspensions. For purposes of orientation, the front of machine A will bethe elevation shown in FIG. 1, while the inner and outer ends of saidmachine will be, respectively, toward the left hand side and right handside of said figure. Machine A comprises a bed 1 supported by legs 2, 3;there being an overhead member 4 mounted on upstanding brackets 5, 6disposed on bed 1. Overhead member 4 has formed on its opposite sidesthereof cooperating longitudinaly progressing ways 7 for slideableengagement thereon of slide bodies 8 formed integral with, and providedat the upper end of, a tailstock 9 whereby the latter is reciprocallymovable along said ways 7. Tailstock 9 contains a bearing 10 forjournalling of the outer end of a mandrel 11, the opposite or inner endof which is rotatably supported by the chuck 12 of a spindle 13 which isrotatable by means of a conventional gear train (not shown) within areduction gear box 14; said train being driven, through suitabletransmitting means by a motor 15 which may be disposed on top gear box14 for compactness.

Tailstock 9 is operatively connected to a fluid pressure actuated motor(not shown) of conventional design, being adapted for either liquid orair; which may be mounted on the rear face of overhead member 4 havingthe usual connecting rods for engaging tailstock 9 to the motor piston.By operation of said fluid pressure actuated motor, tailstock 9 will bemoved outwardly along ways 7 carrying mandrel 11 therewith so as toeffect disengagement of the inner end thereof from chuck 12 for allowingrelease of the work formed on mandrel 11 as will be described more fullyhereinbelow. Said fluid motor may be adapted for timed sequentialoperation to effect a return stroke for restoring mandrel 11 toengagement within chuck 12 for the succeeding work forming operation.

Depending from overhead member 4 is a pair of longitudinallyspaced-apart, transversely extending mounting plates 16, 17 with thespacing between same coinciding with the effective coil-winding lengthof mandrel 11; both of said plates 16, 17 projecting laterally beyondmandrel 11 on either side thereof. Extending between the lower outerportions of mounting plates 16, 17 and being fixed at their ends thereinis a pair of parallel guide rods 18, 19. Intermediate of, and axiallyparallel with, guide rods 18, 19, is a lead screw 20 for presentation inoverlying, vertically spaced relationship to mandrel 11 with the axesthereof being substantially within the same vertical plane; said leadscrew being journalled at its ends within plates 16, 17 in bearingsformed therein.

Lead screw 20 threadedly engages a tapped bore 21 in a bar guide body 22having axially parallel lateral smoothbore openings 23, 23' forrespectively slideably receiving rods 18, 19, which latter stabilize barguide body 22 in its traversing movement consequent to rotation of leadscrew 20. On its forward face, bar guide body 22 carries a bar transferassembly, indicated generally B, which comprises a mounting plate 24having two sets of vertically aligned, slot-like openings, as at 25, 25,which sets are horizontally spaced-apart for extension therethrough ofbolts 26, 26', respectively, whereby a range of vertical adjustabilityis accorded assembly B with respect to its securement upon bar guidebody 22. Rigid with mounting plate 24 and extending forwardly therefromin planar normal relationship thereto is a relatively narrow supportplate 27 within which is formed an elongated aperture 28 extendingsubstantially throughout its length (FIG. for purposes presentlyappearing. At the inner and outer end of support plate 27 there areprovided upstanding end plates 29, 30, respectively, which are rigidwith mounting plate 24, as well as the confronting ends of support plate27. Centrally of end plate 30 is formed an opening 31 through whichprojects the piston 32 of a fluid cylinder 33, said latter being boltedor otherwise fixed to the forward face of end plate 30 whereby piston 32is adapted for movement toward and away from inner end plate 29. Fluidcylinder 33 is an integral part of bar transfer assembly B and isconnected by conduits, as indicated at 34, 35, to a conveniently locatedsource of fluid (not shown); said conduits 34, 35 being of requisitelength and flexibility to permit of effective operation of said cylinder33 during travel of bar guide body 22 along lead screw 20. Piston 32 is,accordingly, axially parallel to, and overlyingly of, aperture 28, andat its inner end is fixedly engaged to the upper portion 36 of a guidecarriage 37. Said upper portion 36 is of greater width than aperture 28so as to provide lateral slide shoulders as at 38, for movement alongsupport plate 27 consequent to actuation of piston 32. Said upperportion 36 of carriage 37 is integral on its under surface with arelatively narrowed, centrally located neck 39 for downward extensionthrough slot 28 for securement, as by a bolt 40, to the under portion ofcarriage 37, generally denoted 41, and which is so formed as to presenta pair of horizontally extending bosses 42, 43 for engaging dependingfingers 44, '45, respectively, on which are suitably mountedfrictionreducing, freely rotatable sleeves 44', 45', respectively; saidbosses 32, 43 being so related that the distance intervening sleeves 44,45' will be adequate to accommodate the diameter of the rod or bar stockfeed to machine A for coil-forming purposes. Between bosses 42, 43 underportion 41 of carriage 37 is provided with an upwardly extending recess46 for reception therein of a roller 47 adapted for free rotation upon ashaft 48 fixed at its ends in the confronting side wall portions of saidrecess 46; the diameter of roller 47 being such as to cause the lowerportion of the same to extend slightly below bosses 42, 43 forcooperating with the said sleeves 44, 45' for conducing to movementbetween the latter of the stock. With reference to FIG. 4, it will beobserved that fingers 44, 45 are presented forwardly of the proximateupper zone of mandrel 11 for work-directing purposes as will be morefully described hereinbelow.

Although in the preferred form of the invention, a servo system willautomatically control the stroke of piston 32 for effecting theindicated relationship between fingers 44, 45 and bar guide body 22,there are shown in the figures detent members which are useful forstroke control (and hence travel of carriage 37 with respect to supportplate 27) when automatic means are not utilized. Accordingly, a block orshim 49 may be used between outer end plate 30 and upper portion 36 ofcarriage 37 for limiting the travel thereof in a direction toward outerend plate 30. Travel of carriage 37 in the opposite direction, that is,toward inner plate 29 may be controlled by an abutment 50 carried on theend of a threaded stem 51 engaged within a tapped opening (not shown) inend plate 29 so that by suitable manipulation thereof, the abutment maybe presented at the requisite location. Such motion limiting members,although mechanically effective, do not conduce to the ease of travelcontrol brought about by the servo system to be described below.

On the under face of bar guide body 22, substantially centrally thereof,there is mounted for rotation about a vertical axis a depending housing52 having a downward 4 ly and inwardly opening recess, as at 53, withinwhich is received a guide roller 54, rotatably mounted upon a shaft 55secured within the outer wall of housing 52, for rotation of said rollerabout an axis parallel to the axis of mandrel 11. In its forward end,roller 54 is provided with a peripheral, shoulder-forming flange, 56 thelower portion of which projects below the bottom portion of housing 52into relatively close proximity to underlying mandrel 11. Housing 52, inits upper or top wall, mounts a short shaft-like member 57 suitablyreceived within a bearing formed in the lower face of bar guide 22 sothat housing 52 together with the associated roller 54, is rotatableabout its vertical axis.

Mandrel 11 is adapted to rotate at a constant, predetermined speed,while lead screw 20 is rotatable at any of various rates so that thelinear velocity of bar guide body 22 will vary directly therewith. Barguide body 22 serves as an immediate pitchcontrol mechanism since itsrate of travel regulates the distance in a longitudinal directionbetween the individual coils of the spring being formed on mandrel 1 1.The means for controlling the angular velocity of lead screw 20 duringthe course of a spring forming operation is fully set forth in ouraforesaid copending patent application Ser. No. 611,210, filed Jan. 3,1967. By reference to said application, it will be seen that lead screw20 projects through a bearing in plate 17 for mounting a pulley 58 aboutwhich is engaged a drive belt 59; said belt being also trained about apulley (not shown) carried on the drive shaft (not shown) of a servomotor (not shown) of a conventional servo mechanism, indicated at S, inthe block diagram set forth in FIG. 6. The aforesaid motor is of thehydraulic type, having a customary servovalve (not shown) which isconnected by conduits to a convenient source of hydraulic fluid,indicated at H in FIG. 6; having pump means. The said servovalve (notshown) is operationally connected to a servo amplifier or controller,designated schematically 60. The output of servo amplifier 60 will befed to the said servovalve, which latter connects hydraulic power sourceH with the motor of servo system S for operation of the latter. Thespeed of rotation of lead screw 20 is directly controlled by servomechanism on system S as the shaft of the related servo motor willrotate at a speed determined by the particular input to servo amplifier60. The various components of the system for effecting operation ofservo mechanism S may be disposed within a console assembly C forconvenient disposition with respect to machine A. A pulse counter of thepreset type, designated 61, being designed to emit a signal afterreceiving an externally selected number of input pulses, is providedwithin said console assembly C; the same having the capacity of countingelevated speeds, such as, within the range of 120,000 pulses per minute,and being of electronic character. Counter 61 is connected to apresettable command voltage circuit 62 also provided within consoleassembly C and incorporating a number of adjustable voltages as obtainedby potentiometers. The presettable potentiometers of command voltagecircuit 62, in accordance with common practice, are engaged, as byrelays, to various presettings of counter 61 so that as thepredetermined pulse is received by counter 61 a circuit will be closedto the related potentiometer to provide the pre-intended output forfeeding to servo amplifier 60, with which said voltage command circuitis connected, for effecting cor relative operation of the respectiveservo motor of servo system S whereby lead screw 20 will rotate at therelated r.p.m.s.

Counter 61 is also connected to a transducer or sensing device 63, whichlatter is operatively engaged to mandrel 11 and being of the angularencoder type for transmission of electric pulses responsive to theangular displacement of mandrel 11. Thus, with each degree of rotationof mandrel 11 a pulse is discharged for reception by counter 61. It willbe seen that the rotary motion of mandrel 11 is used as the commandingsource for the operation of lead screw 20 at varying rates of rotation.Counter 61, being presettable, is adapted to effect operation uponreception of a predetermined signal, such as, closing a switch, relay,or the like; and being capable of effecting a series of operationsthrough receipt of predetermined sequential input signals fromtransducer 63. Upon completion of a particular cycle, counter 61 willreset to in preparation for the succeeding cycle. Counter 61 issynchronized in a well known fashion with the drive system for mandrel11 so that the operation thereof will control the start of the cycle(for formation of the spring and release of the finished springtherefrom) and will cause the resetting of counter 61. It is understoodthat a conventional tachometer is provided within servo system S toassure proper motor speed with respect to the preselected voltage fed toservo amplifier 60.

Also provided within console assembly 0 is a read-out instrument 64 forindicating preset voltages.

A similar system is incorporated within machine A for automaticallycontrolling the movement of carriage 37 whereby the positionment offingers 44, 45 is regulated with respect to bar guide body 22, as thelatter is moved responsively to rotation of lead screw 20. In this phaseof the operation as well, the rotary motion of mandrel 11 provides thecommanding source for the operation, as preset counter 61 is alsoconnected to a presettable command voltage circuit 65, which latter isadapted to feed its output to a servo amplifier 66 for operation of aservo system 67; said latter being also connected to hydraulic powersource H. Said servo system '67 embodies a servovalve for causingpredetermined activation of fluid cylinder 33 to bring about the relatedstroke of piston 32 for causing the respective travel of carriage, whichis broadly indicated in said FIG. 6 as the carriage assembly. Thecomponents 65, 66, 67 of the carriage operating system of the presentinvention correspond structurally and functionally to the relatedcomponents of the system for effecting rotation of lead screw 20, asabove described. However, as observed above, mandrel 11 throughtransducer 63 and preset counter 61 controls when the change of rate ofrotation of lead screw 20 occurs, as well as when carriage 37 and,hence, fingers 44, 45 are moved.

In the operation of machine A, for coiling work W about mandrel 11, barguide body 22 will be at its innermost limit. With carriage 37immediately proximate end plate 29, and with fingers 44, 45 immediatelyadjacent chuck 12 (FIG. 2), the hot rod stock is directed to mandrel 11between fingers 44, 45, for reception upon the upper surface of mandrel11 abutting against the face plate of chuck 12. The initial free endportion of the work W is maintained on mandrel 11 against displacementthrough clamping by a dog d mounted on chuck 12 and projecting outwardlytherefrom. Immediately such clamping action, rotation of mandrel 11 iscommenced with carriage 37 being moved linearly outwardly apredetermined distance from end plate 29 through the system hereinabovedescribed, comprising transducer 63, counter 61, command voltage circuit65, servo amplifier 66, and servo system 67. By such movement ofcarriage 37, fingers 44, 45 will be moved to a predetermined positionrelative to bar guide body 22 for accomplishing several purposes: onebeing to cause the rod stock to be directed beneath roller 54, andagainst shoulder 55 (FIG. 3), for assuring proper control of thetransition pitches of the spring to be formed; and the other being toeffect a presentation of the bar stock to the mandrel at a precalculatedhelic angle, such being the angle developed by the coils of the springin a line established perpendicular to its longitudinal axis. Suchinitial movement of carriage 37 is effected prior to commencement oflinear travel of bar guide body 22; but it is to be particularly noted,however, that the rod stock will make contact with the roller 54 afterthe first turn of the mandrel. The relative travel of carriage 37 withrespect to bar guide body 22 will be dictated by the particular anglebeing developed so that suitable calculations must be programmed intothe console assembly C to effect the length of stroke of piston 32 andthe particular juncture of such stroke during traversing of bar guidebody 22 linearly of lead screw 20. Accordingly, the first movement ofcarriage 37 will be effected prior to rotation of lead screw 20, but anysuch further movements of carriage 37 will occur during travel of barguide body 22. Accordingly, by such action of carriage 37, the helicangle of the coils being formed is appropriately controlled; it beingrecognized that with springs of varying pitch, commensurate movement ofcarriage 37, both toward and away from end plate 30 will be effectedduring the forming operation. The initial movement of carriage 37 priorto rotation of lead screw 20 is a critical action in that, as abovestated, it brings about rod stock controlling action by roller 54 so asto assure maximum accuracy of the transition pitches. It is to beobserved, as by reference to FIG. 4 that roller 54 is presentedimmediately above mandrel 11 which location assures of the requisitecontrol. The unique rockable mounting for roller 54 endows same with thecapacity to follow any helic angle which may be required for the springbeing formed. Shoulder 56 prevents any unauthorized displacement of workW during the forming operation.

As shown in FIG. 6 a read-out instrument 68 is connected to servoamplifier 66 for indicating preset voltages in the system. There is alsoprovided a reference chart, indicated 69, having set forth thereon therequisite spring data for proper presetting of counter 61 and commandvoltage circuits 62 and 65 for the particular coil spring to beproduced. From such chart 69, the length of each pitch of the spring isgiven in degrees (of rotation of mandrel 11) so that the same may be fedto counter 61 to assure of the appropriate signal at the requiredjuncture. Also, there is provided in degrees with respect to rotation ofmandrel 11, the helic angle of the coils being formed so that counter 61may energize the command voltage circuit 65 at the necessary point tobring about movement of carriage 37. Accordingly, counter 61 and commandvoltage circuits 62 and 65 are placed n a fully preset state preparatoryfor the particular forming operation, with lead screw 20 and carriage 37being thus programmed for the given spring. Reference is made to the twoexamples fully set forth and described in our said co-pending patentapplication Ser. No. 611,210 for demonstrating the actual operation ofthe system for utilizing the mandrel as a commanding source fordevelopment of the particular pitches and their respective locatronwithin the spring being formed. From the operatron of such system, theeffectiveness and reliability of the programming method of the presentinvention for effecting requisite operation of carriage 37 is readilyapparent since the components correspond to like elements forcontrolling lead screw 20 with the commandmg source being the same.

Having thus described our invention, What we desire to claim and obtainby Letters Patent is:

1. In a coil spring winding machine having a mandrel for coiling of rodstock thereabout, means for effecting rotation of said mandrel, a rodstock guide body, means causing said guide body to travel in a linearpath longitudinally of said mandrel throughout substantially itseffective coiling length, the improvement comprising rod stock directingmeans moveably provided on said body, and means responsive to rotationof said mandrel effecting movement of said directing means forpreselected disposition of the same with respect to said guide body atpredetermined junctures during rotation of said mandrel.

2. In a coil spring winding machine, the improvement as defined in claim1 and further characterized by said rod stock directing means comprisinga carriage slideably mounted on said rod stock guide body for movementrelatively thereof, fluid motive means engaged to said carriage,

said means responsive to rotation of said mandrel being operativelyconnected to said fluid motive means, and a pair of fingers dependingfrom said carriage for movement therewith.

3. In a coil spring winding machine, the improvement as defined in claim2 and further characterized by said carriage being mounted for movementlongitudinally of said mandrel.

4. In a coil spring winding machine, the improvement as defined in claim3 and further characterized by said fingers being located spacedly fromsaid mandrel in the direction toward the source of the rod stock fedthereto.

5. In a coil spring winding machine, the improvement as defined in claim2 and further characterized by a guide roller carried on said rod stockguide body for movement therewith, means mounting said guide roller forrotation about a normally horizontal axis.

6. In a coil spring winding machine, the improvement as defined in claim5 and further characterized by said guide roller being positioned onsaid guide body for presentation immediately above said mandrel.

7. In a coil spring winding machine, the improvement as defined in claim6 and further characterized by a shoulder formed on said guide rollerfor abutment against stock fed to said machine to prevent unauthorizeddisplacement thereof.

8. In a coil spring winding machine, the improvement as defined in claim6 and further characterized by means mounting said guide roller on saidguide body for permitting rotatability of said roller about a verticalaxis.

9. In a coil spring winding machine, the improvement as defined in claim1 and further characterized by said rod stock directing means comprisinga carriage slidably mounted on said rod stock guide body for movementrelatively thereof, fluid motive means engaged to said carriage, saidmeans responsive to rotation of said mandrel being operatively connectedto said fluid motive means.

References Cited UNITED STATES PATENTS 3,039,706 6/1962 Toth 72-l43 US.Cl. X.R. 72-138, 144

3/1969 Cavagnero 72-438

